Cordless telephone arrangement

ABSTRACT

A cordless telephone arrangement, such as a DECT Business Cordless Telecommunications (BCT) system, comprises a PBX base station ( 1 ) and a plurality of mobile stations in the form of portable handsets ( 2   a,   2   b . . .    2   n ). The handsets themselves include no means for independently dialling a telephone number. Instead of a conventional keypad the handsets each comprise only a single “TALK” key  7 . The PBX  1  is adapted to dial on behalf of each handset in response to an instruction received by radio communication therefrom. In one embodiment the instructions are delivered orally to the handset. In this case the PBX includes a voice recognition device  12 . A voice synthesizer  11  may also be included for returning spoken messages to the handset. The TALK key  7  is used to indicate that the handset is required to make a call, to terminate a call, or to accept an incoming call. Otherwise instructions and messages are largely conveyed between the mobile station and the base station by spoken word using radio communication.

[0001] This invention relates to a cordless telephone arrangementcomprising a base station coupled to a telephone network, and aplurality of mobile stations capable of communicating selectively withother telephones on the network via a radio link with the base station.

BACKGROUND OF THE INVENTION

[0002] At the present time a variety of cordless telephone systems existwithin Europe. For example some countries such as France and UK haveadopted national specifications using low frequencies under 50 MHz. Ananalogue system known as CT1 has been adopted by other countries. Adigital system based on frequency division multiple access (FDMA) knownas CT2, has been developed in the UK. In Sweden the CT3 system has beendeveloped which is a time division multiple access (TDMA) digitalsystem.

[0003] Additionally, the European Telecommunications Standards Institute(ETSI) has proposed a standard cordless system known as Digital EuropeanCordless Telephone (DECT), which offers a quality of communicationscomparable with standard land-line telephones. The DECT concept is oneof versatility of applications at a cost intended to encourage wideavailability and market adoption. The DECT concept includes a definitionof personal portable communications based on small, easy to useterminals. Thus DECT is intended to offer low-power cordless accessbetween a portable terminal and the DECT infrastructure at ranges of upto several hundred meters from the base station.

[0004] Apart from the residential application which would interconnectDECT to a PSTN with the features and responses of a standard fixed-wiretelephone, a DECT Business Cordless Telecommunications system (BCT) isenvisaged that combines the features of a private branch exchange (PBX)with the mobility of cordless telecommunications for both voice andnon-voice applications.

[0005] A common feature of the known cordless systems mentioned above isthat in each case the mobile station, ie the telephone itself,conventionally comprises a user-interface including a display and akeypad having a plurality of buttons or keys which can be depressed bythe user in order to operate the telephone, ie to dial a telephonenumber or perform other functions such as for example to display atelephone number or other data stored in memory. Generally, the keypadcomprises two main sets of keys, namely a first set of alphanumeric keysassociated with alphanumeric data, including the digits 0-9 inclusive,particularly for dialling telephone numbers, but also (optionally) forentering alphanumeric data into the telephone memories, eg a subscribernumber index; and a second set of function keys for enabling previouspredetermined functions or operations. Included in the second set offunction keys, for example, may be a special key for initiating andterminating a telephone call. Another of the function keys may be a menukey, actuation of which enables a variety of pre-set menus to be viewedand selectively enabled. A particular menu option may be selected usinganother key on the keypad.

[0006] Both displays and keypads have certainly gained universalacceptance in the cordless telephone industry and indeed there is a highlevel of commonality of the keypad for telephone applications generally.However, the size and volume of the keypad mechanism and associatedelectronics necessarily contribute to the overall size and weight of thetelephone handset.

[0007] Also, the requirement for a keypad and, possibly a display,imposes significant ergonomic and aesthetic constraint on the overalldesign of a cordless telephone handset.

[0008] In the context of mobile telephones for use inside vehicles,where safety considerations are important, but the weight and volume ofthe overall apparatus are less critical than for portable telephones, itis known to provide a voice recognition facility whereby numbers may bedialled in response to commands uttered by the user without the need formanual dialling. This function is commonly known as voice-activateddialling. It is noted that in known arrangements the voice recognitionfacility is provided within the terminal apparatus and the diallingoperation is performed locally by the mobile telephone apparatus itself.Conventionally, the voice-activated dialling function is provided as anadjunct to the manual dialling facility and hence the telephone isgenerally also provided with a standard keypad. A mobile telephone withvoice-activated dialling is disclosed, for example, in U.S. Pat. No.5,042,063.

SUMMARY OF THE INVENTION

[0009] According to the present invention there is provided a cordlesstelephone arrangement comprising a base station coupled to a telephonenetwork, and a plurality of mobile stations capable of communicatingwith other telephones on the telephone network via a radio link withsaid base station, wherein the base station is adapted to dial atelephone number automatically for a mobile station in response to aninstruction received by radio communication from the respective mobilestation whereby the mobile station may selectively address othertelephones on the network.

[0010] In accordance with the invention dialling is performed remotelyby the base station on behalf of the individual mobile stations inresponse to an instruction sent by radio communication from the mobilestation to the base station. The instruction may be given orally to themobile station, that is to say the user may simply speak the telephonenumber to be dialled. Alternatively, the user may be presented with apredetermined list of telephone numbers, eg shown on a display on themobile station, from which the number to be called may be selected egwith the aid of a movable cursor.

[0011] A cordless telephone arrangement in accordance with the presentinvention thus has the advantage that a telephone number is dialledremotely without the need to enter the number onto a keyboard at themobile station. Indeed in a preferred embodiment the mobile station maycomprise no independent means for dialling a telephone number.Specifically the mobile station need not include a keyboard. Thisenables the mobile station to be more compact and lightweight andpermits much greater freedom in designing the mobile station.

[0012] In the case where the telephone number is dialled by voicecommand from the mobile station there is also no need for the mobilestation to include a visual display, thereby further enlarging the scopefor design freedom.

[0013] In a particular embodiment the mobile station further comprisesmeans including, for example a button actuable by the user, forinitiating a signal to be transmitted to the base station indicating arequest to open communication. Thus the user is required merely to pressa single button to signal to the base station that the dialling facilityis required.

[0014] Suitably the base station may return a message by radiocommunication to the mobile station which has requested communicationacknowledging receipt of the request, and inviting the user to select aservice from a predetermined set of available services. Thepredetermined set of services may include, for example, remote dialling,re-directing an incoming call, storing or retrieving a number in or froma memory etc.

[0015] In one embodiment the base station includes voice synthesizingmeans for conveying a spoken message to the mobile station.Alternatively the different services available may be indicated onvisual display means on the mobile station, and a particular service maybe selected e.g. with the aid of a movable cursor.

[0016] Preferably the base station is adapted additionally to provideautomatically for a mobile station a service other than dialling atelephone number in response to an instruction received by radiocommunication from the respective mobile station. The services providedremotely at the base station may for example include call re-direction,and/or storing or retrieving a number in or from a central memory in thebase station.

[0017] Specifically the mobile station may take the form of a portablehandset and the base station may take the form of a private branchexchange (PBX), for example in the context of a DECT BCT.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Embodiments of the invention will now be described, by way ofexample, with reference to the accompanying drawings in which:

[0019]FIG. 1 is a schematic block diagram of a cordless telephonearrangement in accordance with the preset invention, comprising a basestation and a plurality of mobile stations, and

[0020]FIG. 2 is a schematic block diagram of a different cordlesstelephone arrangement in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0021] The cordless telephone arrangement shown in FIG. 1 comprises abase station 1 connected to the conventional telephone network and aplurality of mobile stations 2 a,2 b, 2 c . . . 2 n in radiocommunication with base station 1. In the context of a DECT BusinessCordless Telecommunications (BCT) system the base station 1 is in theform of a private branch exchange (PBX) and the mobile stations are inthe form of portable handset extensions.

[0022] As shown in FIG. 1 in relation to handset 2 a, each handset 2 a .. . 2n comprises a radio transceiver 3 coupled to an antenna 4. Aconventional speaker 5 and microphone 6 coupled to the transceiver 3 arepresent respectively at the earpiece and the mouthpiece of the handset.The handset 2 a also comprises a button or key 7 present externally onthe handset housing for imitating a signal to indicate that the userwishes to make (or receive a call). The button 7 may be labelled with alegend such as “TALK” or “CALL”, or with a symbol (or icon) such as abow-shaped conventional telephone handset

. When the “TALK” button 7 is pressed the transceiver 3 is activated anda signal is generated under microprocessor control for indicating to thePBX 1 that the mobile station 2 a is requesting that a communicationlink is opened. The request signal is radiated by antenna 4 on thehandset 2 a and received by antenna 8 on PBX 1 when the handset 2 a iswithin range of the PBX 1. At the PBX 1 the antenna 8 is coupled to atransceiver 9 which is in turn coupled to a microprocessor 10. When themicroprocessor 10 detects that the PBX 1 has received a communicationrequest from a specific handset 2 a, the PBX will respond to therespective handset in accordance with a predetermined hand-shakeprotocol. Specifically, the PBX will establish a communications linkwith the particular handset on a unique channel allocation. None of theother handsets 2 b . . . 2 n will be capable of communicating with thebase station on the same channel 5 for the duration of the allocation tothe particular handset 2 a. The PBX 1 responds under control of themicroprocessor by sending a message back to the handset acknowledgingreceipt of the communication request. More particularly the PBX mayinclude a voice synthesizer 11 for generating a spoken message which mayalso invite the user of handset 2 to select a particular service. Forexample, immediately after the communication link is established betweenthe handset 2 a and the PBX 1 the voice synthesizer may generate amessage such as “What service do you require?” which is conveyed byradio communication back to the handset 3 where it is conveyed to theuser through the speaker 5. The user may then issue a spoken instructionor command from a predetermined set of word instructions. The utteredcommand is conveyed by radio from handset 2 a to the PBX 1 where a voicerecognition device 12 is capable of recognising and distinguishing thepredetermined set of instructions. It is noted here that devices forrecognizing uttered word commands are known in the art and in thisregard reference is invited, for example, to PCT patent application WO91/13431 and U.S. Pat. No. 5,042,063. In response to various wordcommands detected by the voice recognition device 13 and under controlof the microprocessor 10 a variety of telephone functions 14 may beselectively enabled locally with the PBX 1 on behalf of the handset 2 a.

[0023] For example, in response to the message “What service do yourequire” heard at the handset 2 a, the user may reply: “STORE”. Thevoice synthesizer 11 in the PBX 11 may return the message “What number?”and the user may then speak the telephone number he wishes to store, eg“One, Two, Three, Four, Five, Six, Seven”. To indicate the end of theentry the user may add, for example the word “STOP” or “END”. Havingdetected the end of the first entry the voice synthesizer 11 in PABXwill generate a further message, such as “What name?”, in reply to whichthe user may speak a name which he wishes to be associated with thenumber to be stored. Additionally or alternatively, the voicesynthesizer may return the message “Which location?”, giving the userthe option to store the number at a particular memory location. If, onthe other hand, he usually simply replies “END” or “STOP” or does notgive any instruction within a predetermined time limit the informationreceived by the PBX 1 will be stored into the next available memorylocation of that portion of the memory 15 present in the PBX 1specifically assigned to the handset 2 a. Thus the telephone numberspoken by the user will be stored together with the associated nameeither at the chosen memory location or at the next available memorylocation in the remote memory 15.

[0024] Once the information entered by the user has been stored in thememory 15, the voice synthesizer 11 may return a message to the handset2 a confirming that the requested service has been performed asrequested and enquiring whether another service is required.

[0025] Now, assuming the user wishes to make an outgoing telephone call,he may initiate the remote dialing function within the PBX 1 by speakingthe instruction “CALL” or “DIAL”. He may then continue by speaking eachof the digits of the telephone number to be dialed. As each digit isrecognised by the voice recognition device 12 in the PBX 1 the number isdialed by the dialing facility encompassed within the general telephonefunctions unit 14 under control of the microprocessor 10 whereby thehandset 2 a may be used to selectively address any other telephone onthe network. Rather than speaking the whole telephone number, if theuser knows that the number is already stored in the PBX memory 15, hemay simply speak either (a) the associated name stored in conjunctionwith the desired number, or (b) the memory location of the desirednumber. Thus each of the following oral commands:

[0026] “Call One, Two, Three, Four, Five, Six, Seven, End”

[0027] “Call Jack, End”

[0028] “Call location One, Five, End”

[0029] spoken into the handset 2 a would have the same effect of causingthe PBX 1 to remotely dial the telephone number 1234567 on behalf of thehandset, assuming that the number 1234567 is stored with the name “Jack”at memory location 15 in the portion of the PBX memory 15 assigned tothe handset 2 a. It will be understood that the memory 15 may also haveportions associated respectively with each of the other handsets 2 b,2 c. . . 2 n, and thus constituting a remote telephone directory for eachhandset.

[0030] Before the dialing operation is commenced by the telephonefunction block 14, the voice synthesizer may return a message to thehandset stating the information received, and requesting confirmation,for example in the following format: “The number you have requested isOne, Two, Three, Four, Five, Six, Seven. Is this correct?” If the userreplies “YES” the dialing operation will proceed. If the user replies“NO” the voice synthesizer may return a prompt such as “Please repeatthe telephone number you require.” After the user has repeated thenumber the PBX will again seek confirmation before commencing thedialing operation.

[0031] Once the dialing instruction has been acted upon by the PBX 1 atelephone call is able to proceed between the handset 2 a and anothertelephone on the network having the number which was dialed.

[0032] Thus the handset 2 a may be used for making calls to any desiredtelephone number although the handset itself does not include aconventional keyboard, nor indeed any independent means for dialingtelephone numbers. On the contrary, the handset 2 a (and each of theother handsets 2 b, 2 c . . . 2 n) comprise only a single, user actuablebutton 7, since all of the functions required for use by the telephoneare available remotely at the PBX 1 and can be actuated by spokencommand from the handset 2 a.

[0033] A call which is in progress may be terminated simply bydepressing the TALK button 7. The radio transmitter in handset 2 a willthereby be disabled.

[0034] Moreover, an incoming call may be directed to the respectivehandset by the PBX in conventional manner. The call may be receivedsimply by pressing the TALK button 7. However, it is preferable that onactuation of the TALK button 7 the call is not connected immediately,but that first an announcement of the call is made. Particularly if theincoming call includes a Calling Line Identification (CLI) signalidentifying the caller the voice synthesizer 11 in the PBX 1 maygenerate an announcement under control of the microprocessor 10, forexample in the following format “Incoming call from 1234567. Do you wishto take the call?”. If the user replies “YES” the call will beconnected, but if the answer is “NO” the PBX will respond with a querysuch as “Do you wish to transfer the call?”. If the answer is “NO” theincoming call will be left ringing and unanswered. On the other hand, ifthe answer is “YES” the PBX 1 will ask “Transfer the call to whichnumber”. The user may then simply speak the telephone number to which heintends the incoming call to be redirected. The voice recognition device12 will respond to the spoken number and cause the incoming call to beredirected by the telephone function facility 14 under the control ofthe microprocessor 10.

[0035]FIG. 2 shows a modified embodiment of a cordless telephonearrangement in which in addition to a talk button 27 the individualhandsets 20 a . . . 20 n additionally comprise a visual display 16 and apair of scroll buttons 17 a, 17 b. Scroll button 17 a bears an upwardlypointing arrow symbol and scroll button 17 b bears a downwardly pointingarrow symbol. In this embodiment the PBX 1 does not include a voicesynthesizer or a voice recognition unit. Hence the PBX 1 is neithercapable of generating voice messages or of understanding spokencommands.

[0036] In this case messages are conveyed by radio communication fromthe PBX 1 to the handset 20 a and displayed in menu format on the visualdisplay 16. A cursor 13 on the display can be moved to point to aparticular option by depressing the UP and DOWN keys 17 a, 17 brespectively. The desired option can then be selected by depressing theTALK

button 27 when the cursor is pointing at the appropriate option.

[0037] Thus for example when the user wishes to make a call he pressesbutton 27. The hand-shake protocol is entered to establish communicationbetween the handset 20 a and the PBX 1 as described above. The PBX 1then returns a message by radio communication to the handset 20 a whichcauses the display 16 to show what options are available eg 1. MAKECALL; 2. TRANSFER NO.; 3. RETRIEVE NO. The user may point to the chosenoption using scroll keys 17 a, 17 b, and confirm the selection bydepressing key 27. If the user selects MAKE CALL the PBX 1 may return afurther message causing the display 16 to show a list of all the namesand/or telephone numbers and/or locations stored in the associatedmemory portion of the PBX memory 15. The user may point to the chosennumber using the scroll keys 17 a, 17 b and confirm the selection bydepressing key 27.

[0038] It will be evident that various means may be shown on handsetdisplay 16 in response to messages received from PBX 1 at differentstages during the making and reception of outgoing and incomingtelephone calls and during the performance of other telephone services.Also, when a menu option is chosen and confirmed by actuation of thehandset key 27 an appropriate instruction will be generated by thehandset under control of a local microprocessor and relayed by radiocommunication to the PBX 1 which will respond accordingly and remotelyperform the requested service on behalf of the handset 20 a in a manneranalogous to that described in connection with the first embodiment.

[0039] In view of the foregoing description it will be evident to aperson skilled in the art that various modifications may be made withinthe scope of the present invention. For example the instructions carriedout by the PBX from the handset may be a combination of spoken commandsand menu selected options. Furthermore the PBX may be adapted to performremotely on behalf of the handset services other than those specificallymentioned herein.

1. A cordless telephone arrangement comprising a base station coupled toa telephone network, and a plurality of mobile stations capable ofcommunicating selectively with other telephones on the network via aradio link with the base station; wherein: a mobile station comprisesmeans for issuing an instruction by radio communication requesting thebase station to dial a desired telephone number; and the base stationcomprises: means for receiving the instruction from the mobile station,and means responsive to said receiving means for dialling the desiredtelephone number to establish communication between the respectivemobile station and the telephone on the network having the desiredtelephone number.
 2. A cordless telephone arrangement as claimed inclaim 1 , wherein the mobile station comprises no independent means fordialling a telephone number.
 3. A cordless telephone arrangement asclaimed in claim 1 , wherein the base station is adapted to dial atelephone number automatically for a mobile station in response to aninstruction uttered to the respective mobile station and received at thebase station by radio communication therefrom.
 4. A cordless telephonearrangement as claimed in claim 1 , wherein the mobile station furtherincludes means for initiating a signal for transmission to the basestation indicating a request to open communication therewith.
 5. Acordless telephone arrangement as claimed in claim 4 , wherein thesignal initiating means include a button actuable by the user.
 6. Acordless telephone arrangement as claimed in claim 4 , wherein the basestation is adapted to send a message by radio communication to themobile station which has requested communication inviting the user toselect a service from a predetermined set of services available.
 7. Acordless telephone arrangement as claimed in claim 6 , wherein the basestation includes voice synthesizing means for conveying a spoken messageto the mobile station.
 8. A cordless telephone arrangement as claimed inclaim 6 , wherein the mobile station includes visual display meansadapted to indicate the predetermined set of services available, andmeans for selecting one of the services indicated on the display.
 9. Acordless telephone arrangement as claimed in claim 1 , wherein the basestation is adapted additionally to provide automatically for a mobilestation a service other than dialling a telephone number in response toan instruction received by radio communication from the respectivemobile station.
 10. A cordless telephone arrangement as claimed in claim1 , wherein the mobile station is in the form of a portable handset. 11.A cordless telephone arrangement as claimed in claim 1 , wherein thebase station is in the form of a private branch exchange (PBX).